How many different types of P-basses were there in 1980? I'll tell you; two. The standard version, and the Precision Special, which had active electronics, gold hardware, and some of them had walnut necks, IIRC. That's it; Fender wasn't making 50 different models of anything back then. There's no way to know which ones are the good ones, though this was near the end of the CBS era, so they are generally thought of as weaker than most other eras (though I'd take one over anything built since as I just liked the mid-late '70's Precisions best). They can be heavy, and the neck pockets weren't always tight.
"But I didn't. I only knew that you'd know that I knew. Did you know that?" - Casanova Frankenstein